No need to remove it. Just wasen't sure from your post.
I just got done cleaning my roof and re-applying some Dicor to some areas, this past weekend.
Had been using the mineral spirits/acetone, but decided to try the Tilex.
Cleaned my fiberglass roof with Tilex this time, as opposed to the auto wash stuff I'd been using, and when some got onto the old Dicor caulk, noticed it cleaned it really well...back to white.
Just used a soft bristle brush on roof, and sprayed some on caulk. Brushed it, let it sit for a minute, and rinsed it off with water.
When roof dried, it was "squeaky" clean with no residue.
New Dicor went on and looks like new.
Yeah, it's a pain in the arse to do every few years, but it pays in the long run.
Sides, two fans, bathroom fan/vent, antenna,, vents...gotta do em all. Can't skimp on it. Have a 4" strip of Eternabond covering the front and rear seam where caps meet roof.
Steve & Cheryl + Charlie & Casey, our furry kids.
2012 Forrest River Lexington 283ts
Toad, 2013 Subaru XV Crosstrek
Camping trips this year so far...8